Slap shots can propel hockey pucks at over 100 mph. During the downswing of a slap shot, the shaft of the golf club flexes thereby storing mechanical energy via the strain of the shaft. When the stick impacts the puck, the strain energy relieves and transfers to the puck via the blade of the stick. Simultaneously, the player is following through by forcefully pushing, with the weight of his body, the stick against the puck. Thus, the combination of force from the follow through, momentum exchange from the impact, and sudden energy release from the shaft propels the puck at much greater velocity than a mere momentum exchange with the blade would, frequently in excess of 100 mph.
Many prior art hockey sticks employ a blade with a male tongue, or tenon, at the shaft end of the blade. The tenon slides into a mating opening in the shaft. The blade is then bonded to the shaft. Then the resulting joint is sanded and painted over to give the assembly a one piece appearance. Unfortunately, the added weight of the joint; the mechanical play inherent in the joint, and the inherent yield of the bonding material adversely affect the play of the stick. Merely sanding and painting the joint cannot mitigate these adverse effects.
Other hockey sticks employ a wooden, tapered portion of the shaft with a blade molded around the tapered portion via resin transfer molding to create a mechanical joint. Regardless of the type of mechanical joint employed, any mechanical joint adversely affects the flex and mechanical integrity of the prior art hockey sticks. For instance, since the mechanical joint must be rigid to secure the blade to the shaft, the designer must add reinforcing material, and hence weight to the blade end of the stick. In the alternative, the designer can accept the weak joint as is. Because the added weight of the reinforced joint lies near the end of the stick, the stick suffers from a disproportionately large increase in moment of inertia, thereby slowing the player's downswing considerably.
Worse yet, the designer, in seeking to optimize shaft flexure, must contend with an inflexible portion of the shaft, the joint, which impedes the optimization of the stick. Thus the energy transfer of a stick with a mechanical joint is considerably less than it ought to be.
Additionally, mechanical joints allow mechanical play and yielding between the blade and shaft. An example of which is the force of impact tending to cause the blade to rotate relative to the shaft. Poor mechanical joints at the blade/shaft transition allow greater blade rotation. Likewise, poor mechanical joints allow translational movement between the blade and the shaft. The movement can occur in both lateral (e.g. parallel to the ice) and vertically (e.g. along the axis of the shaft). While such relative motion may be small, the distance the hockey puck travels amplifies the poor aim caused by such relative movement. Moreover bonding does little to eliminate these problems because the adhesive employed can yield. These shortcomings make repeatable shots difficult with a given stick. They also make performance differences between sticks unpredictable.
Accordingly, it would be desirable to eliminate the mechanical joint between the blade and shaft of a hockey stick. It would also be desirable to provide a method to manufacture a one piece hockey stick with more predictable and superior mechanical properties, particularly at the shaft to blade transition where better torsional and translational control is desirable. It would further be desirable to provide fewer performance differences between different hockey sticks.